U.S. patent number 10,090,647 [Application Number 15/702,608] was granted by the patent office on 2018-10-02 for multi-electrode spark plug.
The grantee listed for this patent is Laurian Petru Chirila. Invention is credited to Laurian Petru Chirila.
United States Patent |
10,090,647 |
Chirila |
October 2, 2018 |
Multi-electrode spark plug
Abstract
A multi-electrode spark plug having a large spark target volume
is disclosed. The spark plugs have a plurality of ground electrode
rods which extend from the base of the spark plug and are twisted
around center electrode to provide a plurality of substantially
equidistant spark points relative to the center electrode. The
spark points are formed in parallel and around the elongated axis
of the spark plug. This configuration enables the spark to be
created where the localized concentration of fuel to air is richer,
such as that which may exist when the engine is operating with
lower revolutions per minute. Test results indicate that
automobiles equipped with the multi-electrode spark plugs exhibit
improved fuel economy, and substantially reduced emissions and air
pollution.
Inventors: |
Chirila; Laurian Petru (Irvine,
CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Chirila; Laurian Petru |
Irvine |
CA |
US |
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Family
ID: |
58240241 |
Appl.
No.: |
15/702,608 |
Filed: |
September 12, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20180123322 A1 |
May 3, 2018 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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15261475 |
Sep 9, 2016 |
9780534 |
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62216925 |
Sep 10, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01T
13/32 (20130101); H01T 13/467 (20130101); H01T
13/20 (20130101); F02P 15/00 (20130101) |
Current International
Class: |
H01T
13/20 (20060101); F02P 15/00 (20060101); H01T
13/46 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Quarterman; Kevin
Attorney, Agent or Firm: Myers Andras LLP Andras; Joseph
C.
Parent Case Text
RELATED APPLICATION INFORMATION
The present application is a continuation of U.S. patent
application Ser. No. 15/261,475, filed Sep. 9, 2016, and entitled
"MULTI-ELECTRODE SPARK PLUG" which claims priority under 35 U.S.C.
Section 119(e) to U.S. Provisional Patent Application Ser. No.
62/216,925 filed Sep. 10, 2015 entitled "MULTI-ELECTRODE SPARK
PLUG" the disclosures of which are incorporated herein by reference
in their entirety.
Claims
What is claimed is:
1. A spark plug comprising: an insulating body having an open bore;
a tubular conductive shell surrounding at least a portion of the
insulating body; a cylindrical center electrode positioned within
the bore of the insulating body, the center electrode having a
central longitudinal axis, the center electrode protruding from the
insulating body forming a terminal end portion adapted to act as a
spark generating portion; and, a plurality of ground electrodes
surrounding the center electrode, each ground electrode having a
base end coupled to the conductive shell and an elongated upper
portion that extends from the base end to a distal end that is
longitudinally spaced from the base end and that also curves around
the central longitudinal axis to form a generally curved path and
provide an elongated inner surface having a radial spark gap
distance from the spark generating portion of the center
electrode.
2. The spark plug of claim 1, wherein the plurality of ground
electrodes further comprises a first set of ground electrodes and a
second ground electrode, the first set of ground electrodes having
a first radial spark distance, the second ground electrode having a
second radial spark distance, the first radial spark distance
differing from the second radial spark distance.
3. The spark plug of claim 2, wherein the second ground electrode
comprises a bi-metal electrode configured to move radially away
from the center electrode with increasing temperature.
4. The spark plug of claim 2 wherein the second ground electrode
having a second radial spark distance comprises a single ground
electrode.
5. The spark plug of claim 1, wherein the generally curved path
comprises a helix formed about the longitudinal axis of the center
electrode.
6. The spark plug of claim 1, wherein the radial spark gap is in
the range of approximately 1.7 millimeters to approximately 4.75
millimeters.
7. The spark plug of claim 1, wherein the spark generating portion
of the center electrode and the elongated upper portions of the
ground electrodes form a three-dimensional spark target volume.
8. The spark plug of claim 7, wherein the spark target volume is
approximately 100 cubic millimeters.
9. The spark plug of claim 7, wherein the spark target volume
comprises a generally open volume adopted for allowing free
propagation of fuel burn.
10. The spark plug of claim 1, wherein one of the plurality of
ground electrodes comprises a conductor having a Positive
Temperature Coefficient which increases the electrical resistance
of said conductor having the Positive Temperature Coefficient with
increasing temperature.
11. The spark plug of claim 1, wherein the plurality of ground
electrodes comprises six ground electrodes.
12. The spark plug of claim 1, wherein the elongated upper portion
of each ground electrodes partially overlaps the base end of an
adjacent ground electrode when viewed along the central
longitudinal axis.
13. A spark plug comprising: an insulating body having an open
bore; a tubular conductive shell surrounding at least a portion of
the insulating body; a cylindrical center electrode positioned
within the bore of the insulating body, the center electrode having
a central longitudinal axis, the center electrode protruding from
the insulating body forming a terminal end portion adapted to act
as a spark generating portion; and, a plurality of cylindrical
ground electrodes surrounding the center electrode, each ground
electrode having a base end coupled to the conductive shell and an
elongated upper portion that extends from the base end to a distal
end that is longitudinally spaced from the base and that also
curves around the central longitudinal axis to form a generally
curved path and provide an elongated inner surface having a radial
spark gap distance from the spark generating portion of the center
electrode, the plurality of ground electrodes having a first set of
ground electrodes and a second ground electrode, the first set of
ground electrodes having a first radial spark distance, the second
ground electrode having a second radial spark distance, the first
radial spark distance differing the from the second radial spark
distance.
14. The spark plug of claim 13, wherein the second ground electrode
comprises a bi-metal electrode configured to move radially away
from the center electrode with increasing temperature.
15. The spark plug of claim 13, wherein one of the plurality of
ground electrodes comprises a conductor having a Positive
Temperature Coefficient which increases the electrical resistance
with increasing temperature.
16. The spark plug of claim 13, wherein the plurality of ground
electrodes comprises six ground electrodes.
17. The spark plug of claim 13 wherein the second ground electrode
having a second radial spark distance comprises a single ground
electrode.
18. The spark plug of claim 13 wherein the spark generating portion
of the center electrode and the elongated upper portions of the
ground electrodes form a three-dimensional spark target volume.
19. The spark plug of 18, wherein the spark target volume comprises
a generally open volume adopted for allowing free propagation of
fuel burn.
20. A spark plug comprising: a cylindrical center electrode having
a central longitudinal axis, the center electrode forming a
terminal end portion adapted to act as a spark generating portion;
and, a plurality of ground electrodes surrounding the center
electrode, each ground electrode having a base and an elongated
upper portion that extends from the base end to a distal end that
is longitudinally spaced from the base end and that also curves
around the central longitudinal axis to form a generally curved
path and provide an elongated inner surface having a radial spark
gap distance from the center electrode.
21. The spark plug of claim 20, wherein the elongated upper portion
of each ground electrode partially overlaps the base end of an
adjacent ground electrode when viewed along the central
longitudinal axis.
22. The spark plug of claim 21 wherein the distal ends of the
elongated upper portion of each ground electrode are spaced from
the base end of the adjacent ground electrode.
23. The spark plug of claim 20 wherein the spark generating portion
of the center electrode and the elongated inner surfaces of the
ground electrodes form a three-dimensional spark target volume.
24. The spark plug of claim 23, wherein the spark target volume is
approximately 100 cubic millimeters.
25. The spark plug of claim 23, wherein the spark target volume
comprises a generally open volume adopted for allowing free
propagation of fuel burn.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to spark plugs for
internal combustion engines and, more particularly, to spark plugs
having multiple ground electrodes forming large, three-dimensional
spark volumes.
2. Description of the Related Art
As is well known, an internal combustion engine is a type of engine
where the expansion of gases produced by combustion applies force
to some component of the engine. In a reciprocating engine, the
piston moves up and down within a cylinder and transfers force from
expanding gas to turn a crankshaft via a connecting rod. The piston
is usually made gas-tight with the cylinder using piston rings. The
combustion chamber consists of the space within the cylinder above
the piston where the burning of the fuel/air mixture occurs.
There are various kinds of internal combustion engines, but the
most common variants are two-stroke and four-stroke, gasoline
powered engines. Such engines have at least one cylinder, and often
have more (e.g., 4, 6, 8, 12 cylinders, etc.). Regardless of the
cycle type and number of cylinders, an air-fuel mixture is
compressed by the piston when it moves in one direction (i.e., the
compression stroke) and then ignited by a spark plug to drive the
piston in the opposite direction (i.e., the combustion stroke).
In a two-stroke engine, the piston completes a full power cycle in
only two strokes because the end of the combustion stroke and the
beginning of the compression stroke happen at the same time, and
because the intake and exhaust functions also happen at the same
time. This is possible because the reciprocating piston blocks and
unblocks intake and exhaust ports that are located in the side wall
of the cylinder.
In a four-stroke engine by contrast, commonly used in automotive
applications, the piston completes four separate strokes per power
cycle, including intake, compression, power, and exhaust strokes. A
four-stroke engine typically uses intake and exhaust valves that
are located in the cylinder head that seal the piston within the
cylinder. The intake and exhaust valves open and close
corresponding ports at the appropriate time and for an appropriate
duration during the intake and exhaust strokes of each four-stroke
power cycle (i.e., intake, compression, power, and exhaust
strokes).
The combustion is accomplished by combining a fuel (e.g., gasoline)
with an oxidizer (e.g., air) to create a fuel-air mixture and then
igniting the fuel-air mixture with an ignition system. In a
traditional vehicle, the ignition system consists of several spark
plugs (one for each cylinder), an ignition coil or other source of
high voltage, a distributor that directs the high voltage from the
ignition coil to an output associated with each spark plug, and
spark plug wires that carry the high voltage from the outputs of
the distributor to each corresponding spark plug and thereby
induces a spark that ignites the surrounding fuel-air mixture.
A spark plug ignites the fuel/air mixture in a gasoline engine.
According to Wikipedia, a spark plug is "[a] device for delivering
electric current from an ignition system to the combustion chamber
of a spark-ignition engine to ignite the compressed fuel/air
mixture by an electric spark, while containing combustion pressure
within the engine."
FIG. 1 shows a typical J-type or single-electrode spark plug 110.
It comprises a metal spark plug shell 120 having with threads 122
that engage a threaded hole in the cylinder head and a single
ground electrode 130 that protrudes from a bottom 121 of the spark
plug shell 120 and extends downward and then inward to provide the
familiar J-shape, an insulated body 140 (e.g., porcelain, high
purity alumina, etc.), a center electrode 150 that is surrounded by
the insulated body 140 and extends from a terminal 160 that mates
with a spark plug wire (not shown) to extend out of the bottom of
the insulated body 140 where it terminates very near to the ground
electrode 130. The space between the center electrode 150 and the
ground electrode 130 defines the "spark gap" 135. If desired, the
gap 135 can be adjusted by bending the ground electrode 130 with a
suitable tool.
In operation, when high voltage is supplied to the center electrode
150, spaced very near the ground electrode 130, the fuel/air
mixture in the spark gap 135 becomes ionized, forming a low
resistance electrical path, and the spark plug "fires" by having a
spark jump the gap between the two electrodes. The spark ignites
the fuel/air mixture located within the combustion chamber, which
rapidly burns, expands, and moves the piston within the
cylinder.
Engineers have used various techniques to try to create a more
homogenous fuel/air mixture that leads to a more efficient engine.
For example, in an effort to create and control turbulence, some
may have modified the configuration of the combustion chamber by
changing the shape of the piston head or internal shape of the
cylinder head, or by increasing the number of valves and
corresponding ports in an attempt to inject the fuel/air mixture in
a spiral pattern, for example. Nonetheless, the fuel/air mixture
remains non-homogenous especially at low engine revolutions per
minute ("RPMs"), consistent with "stop and go" driving typical of
city driving, resulting in imperfect/slow combustion, fouled plugs,
increased emissions/pollution, and lower fuel economy. Cars driven
on highways at more constant speeds (rather than the "stop and go"
type of city driving) keep the engines running above 2000 RPMs and
makes the fuel/air mixture more homogenous and hence the cars will
have less emissions/pollution and will be more efficient.
The market has seen some multi-electrode spark plugs that offer
varying degrees of improvement over a traditional J-type spark
plug, but they still suffer from certain deficiencies. For example,
FIG. 2 shows an exemplary spark-plug 210 that has two ground
electrodes 230 on opposite sides of a center electrode 250. In
similar fashion, FIG. 3 shows another exemplary spark plug 310 that
has four ground electrodes 330 that surround a center electrode
350.
Some believe that the spark plugs 210 and 310 shown in FIG. 2 and
FIG. 3 are not helping more on the "stop and go" type of city
driving but are helping for longer mileage between spark plug
changes due to the fact that when one ground electrode becomes
fouled, another ground electrode will inherently become more
attractive to the spark by virtue of it not yet being fouled.
However, each individual ground electrode circumferentially offer a
limited and very narrow target volume/area for a spark jump, and
each ground electrode extends from the spark plug like a
conventional J-type electrode such that the extension tends to
hinder the spark's access to the adjacent fuel/air mixture.
In addition, the J-type of the electrodes 330 from FIG. 3 and the
way how the electrodes 330 are arranged will slow down the
propagation of the explosion inside the combustion chamber leading
back to slow and inefficient burn of the air fuel mixture,
increasing the emissions and lowering the mileage. Further
increasing the numbers of J-type electrodes to 5, 6, or more
electrodes will shield even more the sparking area from the rest of
the combustion chamber slowing down the propagation of the
explosion and canceling the benefit of having 2, 3, 4, or more
sparking paths.
According, there exists a need for improving the performance of
spark plugs.
SUMMARY OF THE INVENTION
In the first aspect, a spark plug is disclosed. The spark plug
comprises an insulating body having an open bore, a tubular
conductive shell surrounding at least a portion of the insulating
body, and a cylindrical center electrode positioned within the bore
of the insulating body, the center electrode having a central
longitudinal axis, the center electrode protruding from the
insulating body forming a terminal end portion adapted to act as a
spark generating portion. The spark plug further comprises a
plurality of ground electrodes surrounding the center electrode,
each ground electrode having a base end coupled to the conductive
shell and an upper portion forming a generally curved path having a
generally constant radial spark gap distance from the center
electrode and extending partially along the longitudinal axis.
In a first preferred embodiment, the curved path comprises a
portion of a helix formed about the longitudinal axis of the center
electrode. The radial spark gap is preferably in the range of
approximately 1.7 millimeters to approximately 4.75 millimeters.
The spark generating portion of the center electrode and the upper
portions of the ground electrodes preferably form a
three-dimensional spark target volume. The spark target volume is
preferably up to approximately 100 cubic millimeters. The spark
target volume preferably comprises a generally open volume adopted
for allowing free propagation of fuel burn. One of the plurality of
ground electrodes preferably comprises a bi-metal structure
configured to move radially away from the center electrode with
increased temperature. One of the plurality of ground electrodes
preferably comprises a conductor having a Positive Temperature
Coefficient which increases the electrical resistance with
increasing temperature. The spark plug preferably further comprises
an additional fixed ground electrode positioned closer to the
center electrode than the plurality of ground electrodes. The
plurality of ground electrodes preferably comprises six ground
electrodes. Each of the upper portions of the ground electrodes
preferably partially overlap the lower portion of the adjacent
ground electrodes.
In a second aspect, a spark plug is disclosed. The spark plug
comprises an insulating body having an open bore, a tubular
conductive shell surrounding at least a portion of the insulating
body, and a cylindrical center electrode positioned within the bore
of the insulating body, the center electrode having a central
longitudinal axis, the center electrode protruding from the
insulating body forming a terminal end portion adapted to act as a
spark generating portion. The spark plug further comprises a
plurality of cylindrical, rectangular or triangular ground
electrodes surrounding the center electrode, each ground electrode
having a base end coupled to the conductive shell and an upper
portion forming a generally curved path having a generally constant
radial spark gap distance from the center electrode and extending
partially along the longitudinal axis, the ground electrodes
surrounding the center electrode in a circumferentially overlapping
manner. The spark generating portion of the center electrode and
the upper portions of the ground electrodes form a
three-dimensional spark target volume. The spark target volume is
up to approximately 100 cubic millimeters.
In a second preferred embodiment, one of the plurality of ground
electrodes comprises a bi-metal structure configured to move
radially away from the center electrode with increased temperature.
One of the plurality of ground electrodes preferably comprises a
conductor having a Positive Temperature Coefficient which increases
the electrical resistance with increasing temperature. The spark
plug preferably further comprises an additional fixed ground
electrode positioned closer to the center electrode than the
plurality of ground electrodes. The plurality of ground electrodes
preferably comprises six ground electrodes.
In a third aspect, a spark plug is disclosed. The spark plug
comprises a cylindrical center electrode having a central
longitudinal axis, the center electrode forming a terminal end
portion adapted to act as a spark generating portion, and a
plurality of ground electrodes surrounding the center electrode
forming a three-dimensional spark target volume, each ground
electrode having a base and an upper portion forming a generally
curved path having a generally constant radial spark gap distance
from the center electrode and extending partially along the
longitudinal axis.
In a third preferred embodiment, the spark target volume is up to
approximately 100 cubic millimeters. The spark target volume
preferably comprises a generally open volume adopted for allowing
free propagation of fuel burn. Each of the upper portions of the
ground electrodes preferably partially overlap the lower portion of
the adjacent ground electrodes.
The present invention has other objects and features of advantage
which will be more readily apparent from the following description
of the preferred embodiments of carrying out the invention, when
taken in conjunction with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is side, cross-sectional view of a prior art spark plug
having a single J-type ground electrode.
FIG. 2 is a front, perspective view of a prior art spark plug
having two ground electrodes.
FIG. 3 is a front, perspective view of a prior art spark plug
having four ground electrodes.
FIG. 4 is a perspective view of a new Intelligent spark plug in one
or more embodiments.
FIG. 5 is a bottom view of the new Intelligent spark plug in one or
more embodiments.
FIGS. 6A-6C are schematic views of a conventional platinum spark
plug, a conventional iridium spark plug, and one or more
embodiments of the Intelligent spark respectively illustrating the
relative spark target volume for each of the three types of
plugs.
FIG. 7 is a bottom view depicting that a spark produced by the new
Intelligent spark plug tends to "hunt" into a fuel rich
environment.
FIG. 8 is a side, perspective view of a conventional spark plug
before modifications are made to adapt the plug into an Intelligent
spark plug.
FIG. 9 is a side, perspective view of the conventional spark plug
with the ground electrode removed.
FIG. 10 is a side, perspective view of the conventional spark plug
have six holes milled in the spark plug shell in one or more
embodiments.
FIG. 11 is a side, perspective view of six rods positioned in the
six milled holes.
FIGS. 12 and 13 are side, perspective views of the spark plug
receiving an alignment ferrule in one or more embodiments.
FIG. 14 is a side, perspective view of the rods formed and twisted
around the alignment ferrule.
FIG. 15 is a side, perspective view of the Intelligent spark plug
with the ferrule removed in one or more embodiments.
FIGS. 16 and 17 are a bottom and side view respectively of
schematics illustrating manufacturing details for the manufacture
of a six-rod Intelligent spark plug in one or more embodiments.
FIGS. 18A and 18B are a bottom and side view respectively of
schematics illustrating manufacturing details for the manufacture
of a six-rod Intelligent spark plug employing an insert in one or
more embodiments.
FIG. 19A is a perspective view of an insert in an embodiment.
FIG. 19B is a perspective view of the insert positioned in a spark
plug.
FIGS. 20 and 21 show a spark gap dimension/volume perspective for
an Intelligent spark plug with a regular center electrode, when
viewed from inside the piston in one or more embodiments.
FIGS. 22 and 23 show a spark gap dimension/volume perspective for
an Intelligent spark plug with a small center electrode, when
viewed from inside the piston in one or more embodiments.
FIGS. 24 and 25 show a spark gap dimension/volume perspective for a
regular spark plug, the majority of the existing spark plugs, when
viewed from inside the piston.
FIG. 26 is a chart comparing performance of one or more embodiments
of the Intelligent spark to conventional spark plugs.
FIG. 27 is a bar graph comparing the Hydrocarbon emissions of
embodiments of the Intelligent spark plug against conventional
spark plugs.
FIG. 28 is a bar graph comparing the Carbon Monoxide emissions of
embodiments of the Intelligent spark plug against conventional
spark plugs.
FIG. 29 is a bar graph comparing the Nitrogen Oxide emissions of
embodiments of the Intelligent spark plug against conventional
spark plugs.
FIG. 30 is a chart illustrating a Fuel Consumption test for an EPA
Highway 35 miles per hour ("MPH") driving schedule.
FIG. 31 is a chart illustrating a Fuel Consumption test for an EPA
Highway 25 MPH driving schedule.
FIG. 32 is a Dynamometer test performed on an automobile employing
conventional spark plugs.
FIG. 33 is a Dynamometer test performed on an automobile employing
Intelligent spark plugs.
FIG. 34 is a Torque Dynamometer test performed on an automobile
employing conventional spark plugs.
FIG. 35 is a Torque Dynamometer test performed on an automobile
employing Intelligent spark plugs.
FIG. 36 is the test results a Torque Dynamometer tests performed on
an automobile employing conventional and Intelligent spark
plugs.
FIG. 37 is a bottom view of a Low Voltage Intelligent spark plug
employing a bi-metal electrode.
FIG. 38 is a bottom view of a Low Voltage Intelligent spark plug
employing positive temperature coefficient electrode.
FIG. 39 is a bottom view of a Variable Gap Intelligent spark
plug.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In one or more embodiments, a spark plug comprises multiple ground
electrodes surrounding a center electrode forming a large,
three-dimensional spark target volume. The ground electrodes extend
from the base of the spark plug and are twisted around the center
electrode to provide a plurality of substantially equidistant spark
points relative to the center electrode. The spark points are
formed in parallel and around the elongated axis of the spark plug.
This configuration enables a spark to be created where the
localized concentration of fuel to air is richer.
FIG. 4 shows a prototype of a new Intelligent spark plug 10 made
according to a presently preferred embodiment. As shown, the
Intelligent spark plug 10 uniquely has a plurality of ground
electrodes 30, here six, that extend from a bottom surface 21 of
the spark plug's base 20 and overlapping twist around the spark
plug's center electrode 50. This unique configuration for the
ground electrodes 30 provides a plurality of substantially
equidistant spark points, relative to the center electrode 50, both
in parallel with and around an elongated longitudinal axis 60 of
the spark plug 10. The new design creates an infinite number of
sparking paths, of a cylindrical or toroidal shape, around the
center electrode 50 in the center region of the combustion chamber,
without shielding the sparking area for the rest of the combustion
chamber. One or more embodiments provide for an improved spark plug
that automatically creates a high tension voltage jump that more
efficiently ignites the unevenly mixed fuel/air mixture associated
with the "stop and go" type of city driving.
FIG. 5 is a bottom view of the new Intelligent spark plug 10, which
shows how the ground electrodes 30 overlapping twist around the
spark plug's center electrode 50 in one or more embodiments. This
unique arrangement essentially provides a large target area for the
spark jump, while simultaneously providing a relatively unfettered
propagation path for the fuel burn resulting from the spark. In
essence, the overlapping ground electrodes 30 that twist around the
center electrode 50 provide a cylindrical or toroidal target area,
one that surrounds the center electrode and has a fair degree of
length in parallel with the longitudinal axis 60 of the spark plug.
The number of ground electrodes per plug may range from 2 through
10 or more in one or more embodiments.
The operation of the Intelligent spark plug 10 is based on a
theory, confirmed by experimental observation, that the
hydrocarbons in a richer fuel/air mixture provide an electrical
path of least resistance for the spark. It is believed that new
Intelligent spark plug 10 provides much greater efficiency and a
more thorough burn at low revolutions per minute ("RPMs") because
its configuration permits the spark to uniquely "hunt" for the
richest zone of the fuel/air mixture. For engines operating below
about 2,000 RPM, the fuel/air ratio is less uniform (i.e.,
homogenous) that at higher speeds. In such a case, the fuel/air
mixture may be richer on one side of the cylinder than on the
other. The new Intelligent spark plug 10 may help the most,
therefore, for low RPMs, stop and go driving. It may also help
increase efficiencies during the RPM drops associated with
automatic transmission shifting.
As shown in FIGS. 5 and 6, in one or more embodiments, a spark plug
10 comprises an insulating body 40 having an open bore 42, and a
spark plug base 20 (i.e., a tubular conductive shell) surrounding
at least a portion of the insulating body 40. A cylindrical center
electrode 50 is positioned within the bore 42 of the insulating
body 40. The center electrode 50 has a central longitudinal axis
60, the center electrode 50 protruding from the insulating body
forming a terminal end portion 52 adapted to act as a spark
generating portion. The spark plug 10 also has a plurality of
ground electrodes 30 surrounding the center electrode 50, each
ground electrode having a base end 32 coupled to the conductive
shell 20 and an elongated upper portion 34 extending from the base
end to a distal end, forming a generally curved path, and having an
elongated inner surface at a generally constant radial spark gap
distance 72 from the center electrode 50 and, while curving around,
also extending partially along the longitudinal axis 60. As used
herein and as is commonly used in the art, the terms "radial" and
"radially" refers the directions or rays perpendicular to the
longitudinal axis 60. In one or more embodiments, the curved path
comprises a portion of a helix formed about the longitudinal axis
60 of the center electrode 50. In one or more embodiments, the
ground electrodes 30 are cylindrically shaped rods. In one or more
embodiments, the radial spark gap 72 is in the range of
approximately 1.7 millimeters to approximately 4.75
millimeters.
In one or more embodiments, the spark generating portion 52 of the
center electrode 50 and the upper portions 34 of the ground
electrodes 30 form a three-dimensional spark target volume 74 (See
FIG. 6C). The overlapping ground electrodes 30 that twist around
the center electrode 50 provide a cylindrical or toroidal target
area, one that surrounds the center electrode and has a fair degree
of length in parallel with the long axis 60 of the spark plug 10.
In one or more embodiments, the spark target volume 74 is
approximately 100 mm.sup.3 (cubic millimeters). The spark plug may
comprise a plurality of cylindrical, rectangular or triangular
ground electrodes 30 surrounding the center electrode 50 in one or
more embodiments,
As seen in FIGS. 5 and 6, the spark target volume 74 comprises an
generally open volume adopted for allowing free propagation of fuel
burn, as the number and dimensional size of the electrodes provide
a large amount of open, unobstructed space for the fuel/air mixture
to enter the spark target volume and for the fuel burn to propagate
unfettered.
FIGS. 6A-6C are schematic views of a conventional platinum spark
plug 110a, a conventional iridium spark plug 110b, and an
embodiment of the Intelligent spark plug 10 respectively
illustrating the relative spark target volume for each of the three
types of plugs. The conventional spark plugs depicted in FIGS. 6A
and 6B show that the spark target volume is general a small
cylinder having a narrow diameter and a short height. Calculations
suggest that the spark target volume for the conventional spark
plug is about 4 cubic millimeters, and is about 0.4 cubic
millimeters for the Iridium spark plug. The Intelligent spark
target volume 74 is calculated to be about 100 cubic millimeters,
which is 25 and 250 times greater than the conventional and the
Iridium spark plug respectively. Embodiments of the Intelligent
spark plug are able to strike 360 degrees around the center
electrode in a volume that is 20-100 times that of conventional
spark plugs. Embodiments sense where the fuel-air mixture is richer
(in fuel) and strikes at that precise point. The resulting fast and
complete combustion leads to high power, low fuel consumption, and
a huge reduction or even elimination of harmful emissions.
Referring back to FIGS. 2 and 3, the spark target volume for spark
plugs 210 and 310 are not expected to have the large spark target
volumes exhibited by the Intelligent spark plug 10. For example,
the ground electrodes 230 of spark plug 210 terminate with a flat
surface 232 adjacent to the center electrode 250, where the surface
area of the flat surface is similar to that of the ground electrode
130 of conventional spark plug 110. The ground electrodes 230 are
not configured to twist around the center electrode 250 and
therefore do not provide a cylindrical or toroidal target area.
This is likewise true for spark plug 310, which has four electrodes
330 with flat surfaces 332. Hence, the spark plugs 210 and 310 do
not form the large spark target volume of the Intelligent spark
plugs 10.
FIG. 7 shows a depiction of a butane lighter 90 showing the
efficacy of one or more embodiments of an Intelligent spark plug 10
according to a first preferred embodiment. An embodiment of the
spark plug 10 is being repeatedly driven by an ignition source to
generate a spark 11 between its center electrode 50 and a varying
one of its plurality of circumferentially extending ground
electrodes 30. In this confirmatory experiment, a butane lighter 90
and its associated flame 91 are moved around the driven spark plug
10 and one can observe that the spark 11 will jump toward a ground
electrode 30 that is in the vicinity of the richer fuel/air mixture
provided by the flame 91.
FIGS. 8-15 depict an exemplary process for fabricating one or more
embodiments of the Intelligent spark plug 10. The presently
preferred Intelligent plug was fabricated by removing the
conventional J-type ground electrode 130 from a regular spark plug
110, precision drilling six holes 23 in the bottom face 21 of its
base 20. And then welding in six rods 30 that will function as
ground electrodes 30. Specifically, FIG. 8 shows the fabrication
beginning with a conventional spark plug 110 having a J-type ground
electrode 130. FIG. 9 shows the spark plug 110 after its J-type
ground electrode 130 has been removed. FIG. 10 shows the spark plug
10 (it no longer being conventional) after six holes 23 have been
precision drilled into the bottom face 21 of its base 20. FIG. 11
shows the spark plug 10 after six rods 30 that will function as the
ground electrodes 30 have been inserted and welded into the six
holes 23. FIG. 12 shows a ferrule 70 being positioned into the
annular space between the six rods 30 and the center electrode 50.
FIG. 13 shows the six rods 30 surrounding the ferrule 70 while
still straight. FIG. 14 shows the six rods 30 after they were bent
around the ferrule 70 to form the ground electrodes 30 that
surround the center electrode in a circumferentially overlapping
manner. FIG. 15 shows the six ground electrodes 30 at the bottom of
the new Intelligent spark plug 10 with the ferrule 70 removed.
FIGS. 16 and 17 provide presently preferred manufacturing details
for a six-rod Intelligent spark plug 10. The ground electrode 30
measures 11 millimeters in an embodiment, and is embedded into
bottom surface 21 through holes 23. FIG. 17 shows center conductor
50 positioned within the insulating body 40, which is positioned
within the spark plug base 20.
FIGS. 18A and 18B illustrate an "insert-method" approach to
manufacturing an alternative version of a six-rod Intelligent spark
plug 10. Here, an insert 35 having six rods 30 is used. The insert
35 would be fabricated from stainless steel pipe, or tubing, and
could be attached to any existing spark plug after removing its
electrode. Welding the insert 35 in at a few points should be less
expensive than the current method of welding six rods 30 completely
around each rod, after precision drilling six holes in every spark
plug. The insert 35 comprises a lower portion 36, and an insert
shoulder 37 having a larger outer diameter in an embodiment. The
lower portion 36 has a height of 2 millimeters, the insert shoulder
has a height of 1.5 millimeters, and the distance from the bottom
of the insert to the top of ground electrodes 30 measures 10
millimeters in an embodiment. After welding the insert the rods 30
will be bent around the ferrule 70 to form the ground electrodes 30
that surround the center electrode in a circumferentially
overlapping manner.
FIG. 19A is a perspective view of a one-piece insert 80 in one or
more embodiments. The insert 80 comprises a hollow cylindrical base
84 and a plurality of ground electrodes 82. FIG. 19B is a
perspective view of the insert 80 positioned in a spark plug. The
cylindrical base 84 is positioned around the insulating body 40 and
makes electrical contact with the conductive spark plug shell. The
ground electrodes 82 extend from the cylindrical base 84 and
overlapping twist around the spark plug's center electrode 50. This
unique configuration for the ground electrodes 82 provides a
plurality of substantially equidistant spark points, relative to
the center electrode 50, both in parallel with and around an
elongated longitudinal axis of the spark plug. The new design
creates an infinite number of sparking paths, of a cylindrical or
toroidal shape, around the center electrode 50 in the center region
of the combustion chamber, without shielding the sparking area for
the rest of the combustion chamber.
FIGS. 20 and 21 show a spark gap dimension/volume perspective for
an Intelligent spark plug with a regular center electrode, when
viewed from inside the piston in one or more embodiments. The spark
gap for the embodiment depicted in FIG. 20 is 3.75 millimeters. The
height of the ground electrode 30 extending from the bottom surface
21 is 4.3 millimeters in an embodiment.
FIGS. 22 and 23 show a spark gap dimension/volume perspective for
an Intelligent spark plug with a small center electrode, when
viewed from inside the piston in one or more embodiments. The
distance from the center of the center electrode 50 to the
elongated inner surface of the electrodes 30 is 4.7 millimeters,
and the height of exposed ground electrode 30 is 5.5 millimeters in
an embodiment.
FIGS. 24 and 25 show a spark gap dimension/volume perspective for a
regular spark plug 110, the majority of the existing spark plugs,
when viewed from inside the piston. The ground electrode 130
extends 8 millimeters from the plug, and forms a spark gap of 1.3
millimeters for example.
Several tests were made comparing the performance of automobiles
using conventional and Intelligent Spark plugs. The tests included
comparing pollution emissions, fuel economy, and engine performance
for several automobiles. Embodiments of the Intelligent spark plug
may reduce the emission of air pollution from internal combustion
engines.
Cars, scooters, motorbikes, electric power generators, and power
tools are very useful but come with a price in the form of
emissions and air pollution. In 1967 the State of California
created the California Air Resources Board to fight car air
pollution. In 1970, the United States Federal government created
the United States Environmental Protection Agency (EPA). Today most
of the countries around the world regulate car emission to be
measured and to meet specified values. Reducing or eliminating
pollution is important for reducing the effects of climate change,
as some believe that climate change may force 1 out of every 13
species to extinction on average if left unchecked.
Many countries have adopted anti-pollution measures. In Germany
since 2010, Berlin has an "ecological area" in the city center
where only vehicles with appropriate stickers indicating low
emission may enter. In Britain, a congestion toll was implemented
in London city center since 2003. In Greece since 1982, an
alternating traffic system is employed in Athens. In Italy, since
the 1990s, an alternating traffic system in Rome and restricted
traffic areas in historic center are employed. In Portugal, there
are some restricted traffic areas in the historic town center of
Lisbon for vehicles manufactured before 2000. In Scandinavia, there
is a congestion toll in Sweden, bike paths in Denmark, and
congestion tolls and electric cars in Norway. In Paris, the French
capital on Mar. 23, 2015 adopted an emergency traffic-limiting
measure to reduce pollution in the Paris sky, using an alternating
traffic system which stops one in every two cars, scooters, or
motorcycles entering the capital city.
Internal combustion engines emit CO.sub.2 (Carbon Dioxide) which is
not directly harmful, but produces global warming, HC (unburned
Hydrocarbons) which is a major contributor to smog and is linked to
asthma, liver disease, lung disease, and cancer, CO (Carbon
Monoxide) which reduces the blood's ability to carry oxygen and
overexposure is fatal, and NO (Nitrogen Oxides) which is a
precursor to smog and acid rain and may destroy resistance to
respiratory infection.
Several tests were performed on multiple cars to investigate the
performance of automobiles equipped with embodiments of the
Intelligent spark plug. In a first test, a pollution reduction
evaluation test was performed on a 2002 CHRYSLER CONCORDE.RTM. 2.7
Liter V6 engine at a California Smog Check Station. The same car
was tested twice. In one test, conventional spark plugs were
installed, and in the second test, Intelligent spark plugs were
installed.
Tables I and II below present the emission test results for the
automobile installed with conventional spark plugs and Intelligent
spark plugs respectively.
TABLE-US-00001 TABLE I Emission Results With Market Leading Spark
Plugs % % HC CO NO Test RPM CO2 O2 (PPM){grave over ( )} (%) (PPM)
M1: 15 MPH 1628 15.0 0.2 50 0.09 387 M2: 25 MPH 1664 15.0 0.1 4
0.00 49
TABLE-US-00002 TABLE II Emission Results with Intelligent Spark
Plugs % % HC CO NO Test RPM CO2 O2 (PPM){grave over ( )} (%) (PPM)
M1: 15 MPH 1684 14.9 0.1 6 0.00 52 M2: 25 MPH 1669 15.0 0.1 0 0.00
9
FIG. 26 presents a chart summarizing the test results. The chart
lists the emission results for Hydrocarbons, Carbon Monoxide, and
Nitrogen Oxides for the car outfitted with conventional spark plugs
and the car outfitted with Intelligent spark plugs. In this test,
the automobile having embodiments of the Intelligent Spark Plug
outperformed the automobile running conventional spark plugs with
respect to emission of Hydrocarbons, Carbon Monoxide, and Nitrogen
Oxides. FIG. 27 presents the improvement in reduced HC emissions
(PPM) in 3D bar graph format. FIG. 28 presents the improvement in
reduced CO emissions (%) in 3D bar graph format. FIG. 29 presents
the improvement in reduced NO emissions (PPM) in 3D bar graph
format.
In summary, embodiments described herein have been shown to
outperform conventional spark plugs with respect to HC emission
(>800% improvement), CO (>900% improvement), and NO (>700%
improvement). The average improvement in emissions is 8 times
better. The typical differences in pollution emission between
differing brands of conventional spark plugs may be between 5% and
10%.
A second test was performed to determine the increase in fuel
efficiency for engines employing embodiments of the spark plugs
installed in a 2014 TOYOTA CAMRY.RTM. 2.5 Liter, 4 cylinder
gasoline engine. This car has an EPA Highway rating of 35 miles per
gallon ("MPG") at an average speed of 48.3 MPH and a top speed of
60 MPH. The EPA City rating for this car is 25 MPG at an average
speed of 21.2 MPH and a top speed of 56.7 MPH. The combined EPA
rating is 28 MPG. A user's average is 27.3 MPG.
The EPA tests for fuel economy requires a vehicle to run through a
series of pre-determined driving routines referred to as schedules
or cycles that specify the vehicle speed for each point in time
during the tests. FIG. 30 is a chart illustrating a Fuel
Consumption test for an EPA Highway 35 MPH driving schedule. The
test represents a combination of rural and interstate highway
traffic with a warmed-up engine which may be representative of
longer trips in free-flowing traffic. The test lasted 765 seconds,
and each vehicle was driven 10.26 miles for an average speed of
48.3 MPH.
FIG. 31 is a chart illustrating a Fuel Consumption test for an EPA
Highway 25 MPH driving schedule. The test was designed to represent
urban driving where the vehicle is started with the engine cold and
driven in stop-and-go traffic. The test lasts 1874 seconds, and the
vehicle is driven 11.04 miles with an average speed of 21.2 MPH and
a top speed of 56.7 MPH.
A driving test was performed with the 2014 TOYOTA CAMRY.RTM. to
determine the fuel efficiency as a result of using embodiments of
the Intelligent spark plugs described herein. The fuel consumption
was determined by starting with the fuel consumption figures for a
particular vehicle, a 2014 TOYOTA CAMRY.RTM., by driving this
vehicle over a test route while it was equipped with conventional
spark plugs and again when the vehicle was equipped with the
Intelligent spark plugs. The car equipped with conventional spark
plugs exhibited a fuel economy of 27.5 MPG. In contrast, the car
equipped with the Intelligent spark plugs exhibited a significantly
better fuel consumption of 34.7 MPG.
Specifically, the car traveled 2,269 miles through California,
Nevada, and Arizona with highway speeds ranging from 75 to 85 MPH.
When the conventional spark plugs were tested, the average reading
was 27.5 MPG, which is consistent with the EPA rating. When the
Intelligent spark plug was employed, the average gas fuel efficient
was 34.7 MPG, for a 26% increase in fuel economy.
A Dynamometer test measuring power was also performed on the same
2014 TOYOTA CAMRY.RTM., with the best result out of 3 runs were
evaluated. The dyno measurements show horsepower ("hp") produced by
the same vehicle, over a range of speeds (MPH), with conventional
plugs and with the Intelligent spark plugs, the overall graphs and
maximum power readings showing that the vehicle exhibits similar
maximum horsepower readings with the Intelligent spark plugs (that
provided increase fuel consumption in terms of MPG) as compared
with the conventional spark plugs.
FIG. 32 is a Dynamometer test performed on the 2014 TOYOTA
CAMRY.RTM. employing conventional spark plugs. FIG. 33 is a
Dynamometer test performed on the car employing Intelligent spark
plugs. Both graphs are similar showing the engine producing 70
horsepower ("hp") at approximately 20 MPH, and increasing to a
maximum hp at approximately 85 MPH. In summary, the 2014 TOYOTA
CAMRY.RTM. generated 157.96 hp with conventional spark plugs, and
157.08 hp with the Intelligent spark plugs. Hence, the cars
equipped with the Intelligent spark plug generated similar maximum
horsepower as cars equipped with conventional spark plugs.
The generated torque was also measured on the 2014 TOYOTA
CAMRY.RTM.. The dyno measurements that show torque produced by the
same vehicle, over a range of speeds, with conventional plugs and
with the Intelligent spark plugs, the overall graphs and torque
readings showing that the vehicle exhibits a faster increased rate
for torque with the Intelligent spark plugs (that provided increase
fuel consumption in terms of MPG) as compared with the conventional
spark plugs.
FIG. 34 is a Torque Dynamometer test performed on the TOYOTA
CAMRY.RTM. employing conventional spark plugs, and FIG. 35 is a
Torque Dynamometer test performed on an automobile employing
Intelligent spark plugs. FIG. 36 is the test results a Torque
Dynamometer tests performed on the car employing conventional and
Intelligent spark plugs. The car exhibited 175.55 of foot pounds
("ft-lbs") of torque when equipped with conventional spark plugs,
and 277.50 ft-lbs of torque when equipped with Intelligent spark
plugs. When the car was equipped with the Intelligent spark plugs,
the maximum torque increased by 58.07%, and the car exhibited a
faster increase rate, and rose so quickly that the PCM cut the gas
to control the rise according to the pre-programmed rate.
Hence, the first and second tests performed on difference cars
suggest that cars outfitted with the Intelligent spark plug may
exhibit 8 times less harmful emissions, better fuel economy, no
reduction in power, greater torque, and faster, more peppy
response. The overall improvements are shown in terms of less
harmful emission, better fuel consumption, no power reduction,
higher torque, and faster response.
Moreover, it may be easier to mandate the replacement of existing
spark plugs to reduce pollution. In conclusion, the Intelligent
spark plugs may deliver cleaner air, reducing the rate of global
warming, fuel savings, and better a less expensive healthcare.
A third test was performed with two identical 2016 TOYOTA RAV4
.RTM. automobiles with 2.5 L engines. Conventional Iridium spark
plugs were employed in the first car, and Intelligent spark plugs
were employed in the second car. The cars were both driven 193.9
miles after two hours and 33 minutes at an average speed of 76
MPH.
The car equipped with the OEM Iridium spark plugs recorded 27.4
MPG. The car equipped with Intelligent spark plugs recorded 30.2
MPG. Based on the trip computer, the car equipped with the
Intelligent spark plug exhibited a 10.2% fuel consumption
improvement. The fuel economy based on the mileage driven and the
amount of gasoline required to refill the tanks showed a 9.2%
increase in fuel economy for the automobile equipped with the
Intelligent spark plug.
The TOYOTA RAV4 .RTM. car equipped with the Intelligent spark plugs
also underwent a smog check. The results of the smog check are
present in Table III below.
TABLE-US-00003 TABLE III Emission Report for the 2016 TOYOTA RAV4
.RTM. with Intelligent spark plugs % % HC CO NO Test RPM CO2 O2
(PPM){grave over ( )} (%) (PPM) M1: 15 MPH 1388 14.8 0.2 0 0.00 0
M2: 25 MPH 1637 14.8 0.0 0 0.00 0
The smog test revealed that the TOYOTA RAV4 .RTM. car equipped with
Intelligent spark plugs exhibited zero emission for Hydrocarbons.
Carbon Monoxide and Nitrogen Oxides.
In summary, preliminary tests indicate that automobiles equipped
with embodiments of the Intelligent spark may exhibit greater fuel
efficiency, and reduced or eliminated emissions of Hydrocarbons,
Carbon Monoxide, and Nitrogen Oxides.
There are many possible alternatives or improvements. For example,
the center electrode 50 could have a diamond pattern, or otherwise
be knurled, to provide enhanced spark jump opportunities. Along the
same lines, the spiraling electrodes 30 could also be provide with
a similar diamond pattern.
It may also be possible to use a bi-metal arrangement so that the
spiraling ground electrodes 50, when exposed to the heat of
combustion, expand farther apart than initially permitted by the
threaded hole that receives the base of the spark plug. This would
allow for an increased gap between the center electrode and the
spiraling electrodes which may further increase efficiency.
The Intelligent spark plug was also tested on power tools (e.g.,
leaf blower, gas electrical power generator) equipped with
two-stroke and four-stroke gas engines. The emissions of these
engines did reduce substantially but it was also observed,
especially on two-stroke engines, that the spark gaps of the 6
electrodes need to be reduced for a consistent cold start. After
engine was warm, replacing the spark plug with one with the 6
electrodes arranged to a bigger spark gap improved even better the
engine functionality and reduced even more the emissions. This
observation led to the creation of a new version of the Intelligent
spark plug specially designed for engines equipped with sources of
high voltage unable to cover big spark gaps at cold start.
The Low Voltage Intelligent spark plug has one of the electrodes
built from bi-metal material or PTC (Positive Temperature
Coefficient) material. This new electrode will create a smaller
spark gap when the engine is at cold start. After engine start
functioning the heat created inside the combustion chamber will
make the new electrode move away from the center electrode beyond
the rest of the bigger gap electrodes (bi-metal version) or
increase the impedance path of that electrode (PTC version), and
let the rest of the bigger gap electrodes do their job of hunting
the fuel rich areas and ignite in that place for a fast and
efficient combustion.
FIG. 37 is a bottom view of a Low Voltage Intelligent spark plug
401 employing a bi-metal electrode 430. In one or more embodiments,
one of the plurality of ground electrodes comprises a bi-metal
structure configured to move radially away from the center
electrode 50 with increased temperature. When the ambient
temperature is low, electrode 430 is positioned as depicted by
430a. As illustrated schematically, the increased temperature of
the engine changes the position of the bi-metal electrode 430 by
moving the electrode from shape 430a to shape 430b beyond the other
electrodes 30.
FIG. 38 is a bottom view of a Low Voltage Intelligent spark plug
501 employing positive temperature coefficient electrode 530. In
one or more embodiments, one of the plurality of ground electrodes
530 comprises a conductor having a Positive Temperature Coefficient
which increases the electrical resistance with increasing
temperature. The electrode 530 is fabricated from material that
exhibits a positive temperature coefficient. As the temperature of
the plug 501 increases, the impedance of the electrode 530 will
increase such that the electrodes 30 will participate with the
spark firings.
Another alternative embodiment is a Variable Gap Intelligent Spark
Plug with one fixed ground electrode that is closer to the center
electrode (to help the cold start on low voltages) and a number of
4, 5, 6 or more electrodes, all at a greater distance (sparking
gap) from the center electrode. One or more embodiments further
comprise an additional fixed ground electrode positioned closer to
the center electrode than the plurality of ground electrodes.
FIG. 39 is a bottom view of a Variable Gap Intelligent spark plug
601 showing one fixed ground electrode 630 which closer to the
center electrode 50. During experiments, it was observed that even
after the engine cold start moment, when the bi-metal ground
electrode is closer to the center electrodes, the other electrodes
(5 in this case) are still helping on hunting the richer paths and
the engine emissions are lower.
It is believed that once the engine starts running, the compression
and the heat applied to the fuel-air mixture make the sparking gap
difference between the ground electrodes less relevant and the
other 5 electrodes with bigger spark gap will still work on hunting
fuel richer areas due to low impedance path of these areas. During
testing at room temperature, as expected, the spark discharge
occurred all the time between the center electrode and the closer
ground electrode when no propane gas was present. However, once the
propane was introduced into the area with the other 5 ground
electrodes with bigger spark gap, the spark discharge will move
from the initial ground electrode with smaller sparking gap to
whatever electrode with bigger sparking gap is closer to the
propane gas.
The demand for spark plugs is projected to grow significantly for
the foreseeable future. As of 2010, there are over one billion
motor vehicles in use in the world, excluding off-road vehicles and
snowmobiles, scooters and motorbikes, motorboats, and small tools
and construction equipment, which also require spark plugs to
function. U.S. researchers estimate that size of the world's fleets
will double, reaching two billion motor vehicles by 2020. Big
growth is expected from developing economies of the BRICS (i.e.,
Brazil, Russia, India, China, and South Africa). China, the fastest
growing large economy is also the fastest growing market for
automobiles, now with over 100 million vehicles on the road. The
USA currently has the most number of vehicles, with over 250
million vehicles, and China is expected to overtake USA as the
largest automobile market on the planet.
In 2015, the market reached some 1.5 billion vehicles. Two-thirds
or some one billion vehicles are powered by gas engines, and
one-third are powered by diesel, hydrogen, or electricity. Each gas
engine uses four to twelve spark plugs. Considering an average of 5
spark plugs for today's one billion gas engines, there are about
five billion spark plugs in use currently.
By 2020, two billion motor vehicles are expected to be on the road,
increasing at a rate of 100,000,000 vehicles per year. Gas engines
accounts for two-thirds of the total of some 65,000,000 per year
and need an average of five spark plugs. This means that there is a
need of more than 300,000,000 spark plugs just for new gas engines.
There is also an additional spark plug need for replacement and
service, scooters and motorbikes, off-road vehicles and
snowmobiles, motorboats, and small tools and construction
equipment.
The cost of manufacturing a spark plug is approximately US$0.50 in
volume. The wholesale prices range from US$1-US$4 per unit. One
company's starting prices are US$0.96 per unit. The retail price
ranges from US$2.50 up to US$30 for premium plugs, giving a margin
of in excess of US$0.50 per unit. Hence, 300,000,000 spark plugs
can generate a total margin of at least US$150,000,000 per year.
Replacement spark plugs can generate a lot more revenue, especially
if mandated for reducing pollution. There are currently five major
spark plug manufacturers: BOSCH.RTM., NGK.RTM., CHAMPION.RTM.,
DENSO.RTM., and AUTOLITE.RTM..
Although the invention has been discussed with reference to
specific embodiments, it is apparent and should be understood that
the concept can be otherwise embodied to achieve the advantages
discussed. The preferred embodiments above have been described
primarily as spark plugs having multiple ground electrodes forming
a large spark target volume. In this regard, the foregoing
description of the spark plugs is presented for purposes of
illustration and description.
Furthermore, the description is not intended to limit the invention
to the form disclosed herein. Accordingly, variants and
modifications consistent with the following teachings, skill, and
knowledge of the relevant art, are within the scope of the present
invention. The concepts discussed herein may be applied to other
spark creation devices or for applications including internal
combustion engines for automobiles, trucks, power tools, and other
vehicles as well for other types of engines. The embodiments
described herein are further intended to explain modes known for
practicing the invention disclosed herewith and to enable others
skilled in the art to utilize the invention in equivalent, or
alternative embodiments and with various modifications considered
necessary by the particular application(s) or use(s) of the present
invention.
* * * * *